Shelf standard



FIG. 1 is a perspective view of a shelf standard.

FIG. 2 is a front view of the shelf standard.

FIG. 3 is a top view of the shelf standard.

FIG. 4 is a right side view of the shelf standard.

FIG. 5 is a left side view of the shelf standard.

FIG. 6 is a back view of the shelf standard; and,

FIG. 7 is a bottom view of the shelf standard. 

The ornamental design for a shelf standard, as shown and described. 